This application claims the benefit of a Japanese Patent Application No.11-361526 filed Dec. 20, 1999, in the Japanese Patent Office, the disclosure of which is hereby incorporated by reference.
1. Field of the Invention
The present invention generally relates to methods and apparatuses for controlling supply of power and storage media, and more particularly to a power supply control apparatus and a power supply control method which control the supply of power to a computer system via an uninterrupted power supply (UPS), and to a computer-readable storage medium for causing a computer to control the supply of power by such a power supply control method.
2. Description of the Related Art
Conventionally, a power supply control apparatus controls the supply of power via an UPS to a computer system or the like when a power failure or a voltage drop occurs.
FIG. 1 is a system block diagram showing an example of a conventional power supply control apparatus. A computer system shown in FIG. 1 includes an UPS 10, a processing unit 11, and a peripheral unit 12. The processing unit 11 forms the power supply control apparatus.
The UPS 10 is connected between the processing unit 11 and an A.C. power source 14. The UPS 10 detects a power failure when no power is received from the A.C. power source 14. When the power failure is detected, the UPS 10 supplies power from a battery unit thereof to the processing unit 11 and the peripheral unit 12.
The processing unit 11 is connected to the UPS 10 and the peripheral unit 12. The processing unit 11 and the UPS 10 are connected by an UPS interface 13. The processing unit 11 and the peripheral unit 12 are connected via a remote cabinet interface (RCI) 28. Information related to the supply of power to the peripheral unit 12 is notified to the processing unit 11 via the RCI 28.
The peripheral unit 12 is connected to the UPS 10 and the computer system 12, and the power is supplied to the peripheral unit 12 via the UPS 10.
For example, when a power failure occurs at a position indicated by xe2x80x9cxxe2x80x9d in FIG. 1, the UPS 10 detects that no power is supplied from the A.C. power source 14. When no power is supplied from the A.C. power source 14, the UPS 10 notifies information indicating the generation of a power failure to the processing unit 11 via the UPS interface 13. The processing unit 11 which is notified of the information continues to operate using the power supplied from the battery unit of the UPS 10. At the same time, the processing unit 11 receives power supply information from the peripheral unit 12 via the RCI 28.
The processing unit 11 which continues to operate using the power supplied from the battery unit of the UPS 10 monitors the UPS 10 until the power supply from the A.C. power source 14 is restored, within a monitoring time which is set depending on a power supply compensation time of the battery unit of the UPS 10. After the monitoring time elapses, the processing unit 11 carries out a process to normally stop the computer system, and also notifies to the peripheral unit 12 information indicating a disconnection of the power supply. When the peripheral unit 12 is notified of the information indicating the disconnection of the power supply from the processing unit 11, the power supply thereto is disconnected. The power supply to the processing unit 11 is disconnected when the processing unit 11 ends the process of normally stopping the system.
Accordingly, a backup power supply is made by the UPS 10 with respect to the processing unit 11 and the peripheral unit 12 when the power failure occurs, so that the system can be stopped normally.
Next, a description will be given of another example of the conventional power supply control apparatus which uses two power supply systems, by referring to FIG. 2.
FIG. 2 is a system block diagram showing this other example of the conventional power supply control apparatus. In FIG. 2, those parts which are the same as those corresponding parts in FIG. 1 are designated by the same reference numerals, and a description thereof will be omitted. A computer system shown in FIG. 2 includes a processing unit 15, two UPSs 10a and 10b, and peripheral units 16 and 17.
The processing unit 15 is connected to the UPS 10a and the UPS 10b via the respective UPS interfaces 13. The processing unit 15 is also connected to the peripheral unit 16 and the peripheral unit 17 via the respective RCIs 28.
The UPS 10a is connected to an A.C. power source 18, and supplies power to the processing unit 15, the peripheral unit 16 and the peripheral unit 17. On the other hand, the UPS 10b is connected to a A.C. power source 19, and supplies power to the processing unit 15 and the peripheral unit 17.
The peripheral unit 16 receives the power from a single power supply system of the UPS 10a. The peripheral unit 17 receives the power from two power supply systems of the UPS 10a and the UPS 10b. 
Accordingly, two UPSs 10a and 10b are provided in the computer system shown in FIG. 2, so as to cope with a unit which has a power receiving configuration to receive the power from a single power supply system and a unit which has a power receiving configuration to receive the power from two power supply systems. For example, when a power failure occurs at a position indicated by xe2x80x9cxxe2x80x9d in FIG. 2 and no power is supplied to the UPS 10a from the A.C. power source 18, the process to disconnect the power supply in the computer system is not carried out if the other UPS 10b is normal, and the power supply is continued in this case. In this state, the UPS 10a supplies the power from the battery unit thereof.
Next, a description will be given of the internal structure of the UPS, by referring to FIG. 3. FIG. 3 is a system block diagram showing an example of the internal structure of the UPS 10, 10a or 10b. 
In FIG. 3, when an A.C. voltage from an A.C. power supply is input to the UPS, the A.C. voltage is converted into a D.C. voltage by an A.C./D.C. converter 20. The D.C. voltage is supplied via a charger 21 to a D.C./A.C. converter 22 or a battery unit 24. When the D.C. voltage is supplied to the D.C./A.C. converter 22, the D.C. voltage is converted into an A.C. voltage. On the other hand, when the D.C. voltage is supplied to the battery unit 24, the battery unit 24 is charged thereby.
A control circuit 25 checks the voltage between the charger 21 and the battery unit 24, to determine whether or not the A.C. voltage input is normal and whether or not the power is supplied normally from the battery unit 24. When the control circuit 25 detects a power failure based on the D.C. voltage, the control circuit 25 notifies the processing unit 15, for example, via the UPS interface 13. In addition, the control circuit 25 supplies a power supply state indication 26 to a display panel (not shown) of the UPS, so as to display a message, turn on a indicator lamp or the like.
The A.C. voltage from the D.C./A.C. converter 22 is supplied to an external unit such as the peripheral unit 16 or 17, via an A.C. switch 23. Furthermore, when an abnormality is generated in the D.C./A.C. converter 22, the A.C. switch 23 supplies to the peripheral unit the A.C. voltage which is supplied to the A.C. switch 23 via a bypass circuit 27.
Therefore, the UPS 10, 10a or 10b charges the battery unit 24 so that the power can be supplied to the external unit from the battery unit 24 in case of a power failure or the like.
When the power failure occurs at a position indicated by xe2x80x9cxxe2x80x9d in the power supply control apparatus having two power supply systems as shown in FIG. 2, the power is supplied from the battery unit of the UPS 10a since no power is supplied from the A.C. power source 18. On the other hand, the UPS 10b supplies the power from the A.C. power source 19. In this state, the processing unit 15 continues to operate without carrying out a process to stop the system.
As a result, there is a problem in that, even though the power is supplied to the processing unit 15 from the A.C. power source 19, the power from the battery unit of the UPS 10a is also consumed.
Accordingly, it is a general object of the present invention is to provide a novel and useful power supply control apparatus, power supply control method and storage medium, in which the problem described above is eliminated.
Another and more specific object of the present invention is to provide a power supply control apparatus, a power supply control method and a computer-readable storage medium, which can efficiently cope with a power failure by effectively utilizing an UPS in an information processing system such as a computer system which includes at least one power supply system.
Another and more specific object of the present invention is to provide an apparatus for controlling supply of power to an electronic device coupled thereto via one or a plurality of uninterrupted power supply units each receiving power from a corresponding external power source or including a battery unit, each of said uninterrupted power supply units outputting power failure information when no power is received from the corresponding power source, where the apparatus comprises a first controller controlling input of power from the one or plurality of uninterrupted power supply units to the electronic device, and a second controller controlling said first controller in response to the power failure information received from at least one of the uninterrupted power supply units. According to the apparatus of the present invention, it is possible to efficiently cope with a power failure by effectively utilizing the uninterrupted power supply units in an information processing system such as a computer system which includes at least one power supply system.
A further object of the present invention is to provide a method for controlling supply of power to an electronic device coupled thereto via one or a plurality of uninterrupted power supply units each receiving power from a corresponding external power source or including a battery unit, each of said uninterrupted power supply units outputting power failure information when no power is received from the corresponding power source, where the method comprises the operation of controlling input of power from the one or plurality of uninterrupted power supply units to the electronic device in response to the power failure information received from at least one of the uninterrupted power supply units. According to the power supply control method of the present invention, it is possible to efficiently cope with a power failure by effectively utilizing the uninterrupted power supply units in an information processing system such as a computer system which includes at least one power supply system.
Another object of the present invention is to provide a computer-readable storage medium which stores a program for causing a computer to control supply of power to an electronic device coupled thereto via one or a plurality of uninterrupted power supply units each receiving power from a corresponding external power source or including a battery unit, each of said uninterrupted power supply units outputting power failure information when no power is received from the corresponding power source, where the computer-readable storage medium comprises first means for causing the computer to control input of power from the one or plurality of uninterrupted power supply units to the electronic device, and second means for causing the computer to control said first means in response to the power failure information received from at least one of the uninterrupted power supply units. According to the computer-readable storage medium of the present invention, it is possible to efficiently cope with a power failure by effectively utilizing the uninterrupted power supply units in an information processing system such as a computer system which includes at least one power supply system.